#include using namespace std; vector solve(vector A,int n) { // Return the sum of S(S(A)) modulo 10^9+7. vector< long int> trans(1000000); int j,l=0; for(int k=0;k> n; vector a(n),result(1000000),result2(1000000); for(int a_i = 0; a_i < n; a_i++){ cin >> a[a_i]; } result = solve(a,n); for(int a_i = 0; result[a_i] != 0; a_i++){ n2++; } result2=solve(result,n2); long int sum=0; for(int i=0;result2[i]!=0;i++){ sum=sum+result2[i]; if(sum>=1000000007) sum=sum%1000000007; } cout << sum << endl; return 0; }